Hydraulic unit for anti-lock automobile brake systems and method for producing the same

ABSTRACT

A hydraulic assembly for slip-controlled brake systems of motor vehicles, having a valve block with receiving bores, each for a hydraulic part of electromagnetically actuated valves, each of which contains magnetically active elements and a respective electric part having an electric coil encompassing the valve dome, a coil housing, and a washer that is contained at least indirectly in the coil housing, on the side oriented toward the hydraulic part. The washers of at least some of the valves are interconnected to form a multi-washer component. The production of the hydraulic assembly then includes the production of a structural unit, which supports the respective electric parts of at least some of the valves, by connecting the coil housing to the associated washers of the multi-washer component, and the placement of this structural unit onto the valve block by introducing the valve domes into through openings of the washers.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a 35 USC 371 application of PCT/DE 02/00368 filed onFeb. 1, 2002.

BACKGROUND OF THE INVENTION

1 Field of the Invention

The invention is directed to an improved hydraulic assembly forslip-controlled brake systems of motor vehicles and to a method for itsproduction.

2 Description of the Prior Art

A hydraulic assembly of the type with which this invention is concernedis known from EP 0 720 551 B1 and has a valve block with receivingbores, each for containing the hydraulic part of respectiveelectromagnetically actuated valves, each of which contains magneticallyactive elements such as an armature and magnetic core of the valve domethat contains the hydraulic part and that protrudes in the extension ofthe receiving bore, up from a delimiting plane of the hydraulic block.The valves also each have an electric part, which is slid onto the valvedome, and have an electric coil that encompasses this valve dome, a coilhousing, and a washer that is contained in the coil housing, on the sideoriented toward the delimiting plane. The electric part is centered inrelation to the hydraulic part of the valve, among other things by thewasher being slid onto a bushing that is caulked into the receivingbore. Usually six or twelve coils are used for each hydraulic assembly;in order to assemble the electric part of the valves, the washers foreach coil are individually press-fitted into a bottom opening of theassociated coil housing, and then the coil housing and the coil togetherare slid onto the valve dome from above until the washer comes intocontact with the bushing.

SUMMARY AND ADVANTAGES OF THE INVENTION

Because of the interconnected washers, when the hydraulic assemblyaccording to the invention is assembled, first the coil housings thatcontain the coils are placed onto the associated washers and then theresulting electric portions of all of the valves that make up thehydraulic assembly are mounted as a single unit onto the valve block. Incomparison to the prior method, this has the advantage of a shorterproduction time since it combines a number of similar production steps.

Advantageous modifications and improvements of the invention arepossible by means of the measures taken in the dependent claims.

A particularly preferable modification of the invention provides thatthe washers are disposed next to one another, essentially in a plane,and are interconnected by bridge pieces, which in the assembled state,protrude through radial notches in the ends of the coil housings in sucha way that the faces of the washers oriented toward the hydraulic partof the valves are flush with the end surface of the associated coilhousing. Then the bottom surface of the multi-washer component thatsupports the coil housings constitutes a planar surface, which can comeinto flat contact with the likewise planar surface of the valve block,which results in an improved magnetic flux.

Another preferred embodiment provides that at least some of the bridgepieces are embodied as elastically and/or plastically deformable. Thisallows valve domes, which may have been installed into the valve blockin positions that deviate from the perpendicular, to be tolerancecompensated by virtue of the washers being oriented at angles to oneanother.

According to one modification, at least some of the bridge pieces havefastening elements such as screw eyelets or stop faces for hold-downelements or ribs that protrude from a control unit housing, which can befastened to the valve block, and that are used for affixing themulti-washer component.

BRIEF DESCRIPTION OF THE DRAWINGS

An exemplary embodiment of the invention is described in detail hereinbelow, in conjunction with the drawings, in which:

FIG. 1 shows a longitudinal section through an electromagneticallyactuated valve that is closed when without current, which is part of apreferred embodiment of the hydraulic assembly according to theinvention; and

FIG. 2 shows a schematic depiction of a multi-washer component with acoil housing of the valve from FIG. 1, shortly before assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT

For scale reasons, FIG. 1 shows only one electromagnetically actuatedvalve 1 of a hydraulic assembly for slip-controlled brake systems ofmotor vehicles that includes a total of twelve such valves. The valve 1is comprised of a hydraulic part 2 and an electric part 4. The hydraulicpart 2 is received and fastened in a stepped receiving bore 6 of a valveblock 8 . In the extension of the receiving bore 6, a valve dome 10 ofthe hydraulic part 2 protrudes up from a delimiting plane 12 of thevalve block 8. The electric part 4 is slid onto the valve dome 10.

The hydraulic part 2 contains a thin-walled cylindrical guide sleeve 14inside of which an axially mobile armature 16 with a closing element 18is guided. A valve body 20 is press-fitted into the bottom of the guidesleeve 14 and is provided with a valve seat 22 for the closing element18. A magnetic core 24 is fastened into the opposite end of the guidesleeve 14 by means of welding 26, with a narrow air gap 28 left open onits side oriented toward the armature 16. A closing spring 32 that issupported against the magnetic core 24 is contained in a blind bore 30of the armature 16.

A bushing 34 made of soft magnetic material is supported on the middlepart of the guide sleeve 14 by means of a flange 36, and is fastenedthere for example by means of welding 38, the flange 36 being held in abore step 40 of the receiving bore 6 by means of a caulk 42. A bottomsurface 44 of the flange 36 rests against the bottom of the bore step40, while the other surface 46 is overlapped by a material bead 48,which has been produced using material displaced from the wall of thebore. The caulk 42 secures the position of the hydraulic part 2 of thevalve 1 in the valve block 8.

After the hydraulic part 2 is fastened into the valve block 8, theelectric part 4 of the valve 1 is slid onto the valve dome 10 and has anelectric coil 50, which encompasses this valve dome 10 in the vicinityof the magnetic core 24. The coil 50 is contained in a coil housing 52,the bottom of which has a washer 54 made of soft magnetic materialpress-fitted into it. Connecting pins 56 of the coil 50 protrudeperpendicularly upward through the top wall of the coil housing 52. Thecoil housing 52 preferably encompasses the magnetic core 24 withoutplay, and with the washer 54, encompasses the bushing 34 of thehydraulic part 2, and is thus centered on it.

When the coil 50 is without current, the closing spring 32 holds theclosing element 18 in contact with the valve seat 22. When the coil 50is excited, the bushing 34 as well as the magnetic core 24 and the coilhousing 52, contributes to conducting the magnetic flux to the armature16 of the hydraulic part 2. The magnetically active magnetic core 24then generates magnetic forces that push the axially mobile armature 16into the open position of the valve 1.

FIG. 2 shows the coil housing 52 of the valve 1 in a state shortlybefore it is mounted onto the associated washer 54. Each of the twelvevalves 1 of the hydraulic assembly is associated with such a washer 54;the washers 54 are disposed next to one another, essentially in a plane,and are interconnected by means of bridge pieces 58. The bridge pieces58 and the washers 54 then combine to form a preferably one-piece,planar multi-washer component 60, which is comprised for example of astamped sheet metal part and in which each washer 54 is connected toanother washer 54 by means of at least one bridge piece 58. The positionof the individual washers 54 within the multi-washer component 60 isselected so that central through openings 62 of the washers 54 can beaxially aligned with the associated valve domes 10 protruding from thevalve block 8.

The thickness of the bridge pieces 58 is preferably identical to thethickness of the washers 54. At least some of the bridge pieces 58 a canbe designed to be elastically and/or plastically deformable in order topermit tolerance compensation of valve domes 10, which may have beencaulked into the valve block 8 in positions that deviate from theperpendicular. These bridge pieces 58 a then have, for example, areduced cross section on one side in comparison to the washers 54. Inaddition, at least some of the bridge pieces 58 b can be provided withfastening elements such as screw eyelets 64 in order to fasten themulti-washer component 60 to the valve block 8. Alternatively or inaddition to this, the bridge pieces can be provided with stop faces forhold-down elements or ribs that protrude from a control unit housing,not shown, and that are used for affixing the multi-washer component 60in its installation position.

If the hydraulic part 2 of the valves 1 is already caulked into theassociated receiving bore 6, then the coil housings 52 and the coils 50are sequentially press-fitted with their bottom openings 66 onto theassociated washers 54 of the multi-washer component 60 until a face 68of each washer 54 oriented toward the hydraulic part 2 of the valve 1 isflush with the end surface 70 of the associated coil housing 52 so thatthe multi-washer component 60 has a planar bottom surface. In order toaccomplish this, the ends of the coil housings 52 are provided withradial notches 72 whose cross sections correspond essentially to thoseof the bridge pieces 58 in the vicinity of the respective washers 54 andthe bridge pieces 58 pass radially through these notches 72, as alsoshown in FIG. 1. Assembling these parts produces a structural unitcomprised of the electric parts 4 of all of the valves 1 of thehydraulic assembly secured to the multi-washer component 60.

In a subsequent step, this structural unit is placed onto the valveblock 8 from above by introducing the valve domes 10 protruding up fromthe valve block 8 into the through openings 62 of the associated washers54; the washers 54 preferably engage with a press fit around theassociated bushings 34 caulked into the receiving bores 6 and themulti-washer component 60 comes into contact with its planar bottomsurface on the delimiting plane 12 of the valve block 8, as shown inFIG. 1.

Preferably, a sheet metal electric connecting grid 74, which can beconnected to a current source, is provided to supply current to all ofthe coils 50 and is designed so that it can be placed onto theconnecting pins 56 of the coils 50. To this end, shoes 76 with U-shapedcross sections that open toward the connecting pins 56 are provided atlocations on the connecting grid 74 disposed opposite from theconnecting pins 56; these shoes 76 embrace the connecting pins 56 andare welded to them. Alternatively, the individual connecting pins 56 canalso be connected to one another and to a current source by means ofpin-and-socket connecters. The assembled structural unit comprised ofthe multi-washer component 60 and the coil housings 52 is enclosed by acontrol unit housing, not shown, which can be fastened to the valveblock 8. Ribs or hold-down elements can protrude from the control unithousing, toward the multi-washer component 60 and can exert pressurefrom above onto some of the bridge pieces 58, thus securing themulti-washer component 60 in position, together with the coil housings52.

The foregoing relates to preferred exemplary embodiments of theinvention, it being understood that other variants and embodimentsthereof are possible within the spirit and scope of the invention, thelatter being defined by the appended claims.

1. In a hydraulic assembly for slip-controlled brake systems of motorvehicles, having a valve block (8) with receiving bores (6), each for ahydraulic part (2) of electromagnetically actuated valves (1), each ofwhich contains magnetically active elements, such as an armature (16)and a magnetic core (24) of a valve dome (10) that contains thehydraulic part (2), and a respective electric part (4), which is slidonto the valve dome (10) and has an electric coil (50) encompassing thisvalve dome (10), a coil housing (52), and a washer (54) that iscontained at least indirectly in the coil housing (52), on the sideoriented toward the hydraulic part (2) which closes a magnet circuitfrom the magnetic core (24) to the armature (16) via the coil housing(52), the improvement wherein the washers (54) of at least some of thevalves (1) are interconnected to form a multi-washer component (60), thewashers (54) being disposed next to one another, essentially in a plane,and connected to one another by means of bridge pieces (58, 58 a, 58 b),wherein in the assembled state, the bridge pieces (58, 58 a, 58 b)protrude through radial notches (72) provided in ends of the coilhousings (52) in such a way that faces (68) of the washers (54) orientedtoward the hydraulic part (2) of the valves (1) are flush with an endsurface (70) of the associated coil housing (52).
 2. The hydraulicassembly according to claim 1, wherein each washer (54) is connected toanother washer (54) by means of at least one bridge piece (58, 58 a, 58b).
 3. The hydraulic assembly according to claim 2, wherein the washers(54) and bridge pieces (58, 58 a, 58 b) constitute a preferablyone-piece multi-washer component (60).
 4. The hydraulic assemblyaccording to claim 3, wherein at least some of the bridge pieces (58 a)are embodied as elastically and/or plastically deformable.
 5. Thehydraulic assembly according to claim 2, wherein at least some of thebridge pieces (58 a) are embodied as elastically and/or plasticallydeformable.
 6. The hydraulic assembly according to claim 2, wherein atleast some of the bridge pieces (58 b) have fastening elements such asscrew eyelets (64) or stop faces for hold-down elements or ribs thatprotrude from a control unit housing, which can be fastened to the valveblock (8), and that are used for affixing the multi-washer component(60).
 7. The hydraulic assembly according to claim 1, wherein thewashers (54) and bridge pieces (58, 58 a, 58 b) constitute a preferablyone-piece multi-washer component (60).
 8. The hydraulic assemblyaccording to claim 7, wherein at least some of the bridge pieces (58 a)are embodied as elastically and/or plastically deformable.
 9. Thehydraulic assembly according to claim 8, further comprising connectingpins (56) disposed on the end surface of the coil housing (52) orientedaway from the valve block (8), and a shared electric connecting grid(74) which can be placed onto the connecting pins (56) of the valves(1).
 10. The hydraulic assembly according to claim 7, wherein at leastsome of the bridge pieces (58 b) have fastening elements such as screweyelets (64) or stop faces for hold-down elements or ribs that protrudefrom a control unit housing, which can be fastened to the valve block(8), and that are used for affixing the multi-washer component (60). 11.The hydraulic assembly according to claim 7, further comprisingconnecting pins (56) disposed on the end surface of the coil housing(52) oriented away from the valve block (8), and a shared electricconnecting grid (74) which can be placed onto the connecting pins (56)of the valves (1).
 12. The hydraulic assembly according to claim 1,wherein at least some of the bridge pieces (58 a) are embodied aselastically and/or plastically deformable.
 13. The hydraulic assemblyaccording to claim 12, wherein at least some of the bridge pieces (58 b)have fastening elements such as screw eyelets (64) or stop faces forhold-down elements or ribs that protrude from a control unit housing,which can be fastened to the valve block (8), and that are used foraffixing the multi-washer component (60).
 14. The hydraulic assemblyaccording to claim 12, further comprising connecting pins (56) disposedon the end surface of the coil housing (52) oriented away from the valveblock (8), and a shared electric connecting grid (74) which can beplaced onto the connecting pins (56) of the valves (1).
 15. Thehydraulic assembly according to claim 1, wherein at least some of thebridge pieces (58 b) have fastening elements such as screw eyelets (64)or stop faces for hold-down elements or ribs that protrude from acontrol unit housing, which can be fastened to the valve block (8), andthat are used for affixing the multi-washer component (60).
 16. Thehydraulic assembly according to claim 1, further comprising connectingpins (56) disposed on the end surface of the coil housing (52) orientedaway from the valve block (8), and a shared electric connecting grid(74) which can be placed onto the connecting pins (56) of the valves(1).